Flashlight and shutter synchronizer having adjustable switch actuating member



F. A. G. PIRWITZ FLASHLIGHT AND SHUTTER SYNCHRONIZER HAVING ADJUSTABLESWITCH ACTUATING MEMBER Sept. 27, 1949.

2 Sheets-Sheet 1 Filed May 16, 1946 Fr/baisr/MA. fiuszavP/rw/iz IINVENTOR ATTORNEY Sept. 27, 1949. wn-z 2,483,023

FLASHLIGHT AND SHUTTER SYNCHRONIZER HAVING ADJUSTABLE SWITCH ACTUATINGMEMBER Filed May 16, 1946 2 Sheets-Sheet 2 Fr/edr/bh A-Guszav P/rm'zz INVENT OR ATTORNEY Patented Sept. 27, 1949 FLASHLIGHT AND SHUTTER SYNCHRO-NIZER HAVING ADJUSTABLE SWITCH ACTUATING MEMBER Friedrich A. GustavPirwitz, Rochester, N. Y., as-' signor to Wollensak Optical Company,Rochester, N. Y., a corporation of New York Application May 16, 1946,Serial No. 670,266

5 Claims.

This invention relates to a flashlight and shutter synchronizer, withmore particular reference to the type of photographic shutter in which aflashlight circuit is closed by a spring-operated synchronizer that isset and released by a shutter master lever, and it has for its purposeto provide eificient and practical adjusting mechanism adapted to lampshaving different lag characteristics, whereby the flashlight circuit canbe closed at any predetermined point either before or after initiatingopening of the shutter so as to insure maximum light intensity at theexact instant when the shutter is fully open.

More specifically, the invention has for its object to afiord a simple,rugged, and durable mechanism that can be economically manufactured, andmakes possible the required adjustability of the instant of flashlightcircuit-closing in relation to shutter opening, while utilizing a switchthat is fixedly mounted on the shutter housing and into close engagementand holding them engaged L for the necessary length of time to insureproper lighting action.

An additional purpose of the invention is to afford a mechanism thatinstead of adjusting the switch or switch contacts to vary the time offlashlight circuit-closing, accomplishes this objective through theinstrumentality of an adjustable actuating element that engages a switchcontact and is operated by the synchronizer in any position throughoutits range of adjustment.

A further object of the invention is to afford an adjustable switchcontrol mechanism that is of simple and economical construction, andwhich operates with uniform accuracy and dependability after the partshave been subjected to considerable wear, thus enhancing the life andreliability of the mechanism.

Still another purpose of the invention is to provide a mechanism with aminimum number of parts, in which an actuating lever is adjustable alongthe path of movement of a spring-operated synchronizer and has a camsurface located in the path of the synchronizer to be engaged and movedthereby, the lever having another surface engaging one of the switchcontacts for actuating it to close the circuit when engaged by thesynchronizer in any selected position of adjustment.

An additional object of the invention is to eliminate the use ofelongated, highly flexible and delicate contacts, or other type ofswitch mounted on an adjustable insulated block, and to accomplish theobjective through the use of a fixed switch consisting of more rigidcontacts insulated from the housing and actuated by a relativelypowerful lever that is adjustable to vary the instant of circuit closingin relation to opening the shutter.

To these and other ends, the invention consists in the construction andarrangement Of parts that will appear clearly from the followingdescription when read in conjunction with the accompanying drawings, thenovel features being pointed out in the claims following thespecification.

In the drawings:

Fig. 1 is a plan view, partially broken away, showing the application ofthe invention in a preferred embodiment to a photographic shutter, withthe master lever and spring-operated synchronizer innormal position andthe flashlight circuit switch actuating lever adjusted to zero positionfor a lamp having no appreciable lag;

Fig. 2 is an enlarged detail view, partially broken away, illustratingthe position of the synchronizer when moved to set position and held byits locking device, ready for operation upon release, and with theactuating lever adjusted to zero position as in Fig. 1;

Fig. 3 is a detail view in elevation of the adjustable support on whichthe actuating lever is mounted;

Fig. 4 is a detail view in elevation of the actuating lever removed fromthe adjustable support;

Fig. 5 is a detail enlarged view with the synchronizer in set positionas in Fig. 2, and with the actuating lever adjusted to operate theswitch and close the flashlight circuit in advance of opening theshutter, to accommodate a 20 millisecond lamp, and

Fig. 6 is a view similar to Fig. 5, showing the position of thesynchronizer and the actuating lever at the instant when the contactsare engaged and the flashlight circuit closed.

This invention is in the nature of an improvement on the mechanismdisclosed in my Patent No. 2,404,526, July 23, 1946, in which there is aspring-operated master lever controlling the shutter and adapted to becocked by a setting lever and released by a trigger, the master lever inturn controlling a pivoted spring-actuated synchronizer that is moved bythe master lever to set position and held by a locking member that inturn is released by the master lever during return movement of thelatter. The structure of the present application is similar to the partsjust described and it is therefore unnecessary to disclose in detail thearrangement and operation of the master lever or the manner in which itcontrols the synchronizer.

In the pending application above mentioned, a flashlight circuit-closingswitch is mounted on an adjustable support for engagement by thesynchronizer, and adjustment of the switch support changes the positionof the switch in relation to the synchronizer so as to vary the time ofclosing the flashlight circuit in relation to opening or the shutter,whereas in the present invention, the switch is stationarily mounted onthe shutter housing and the required variation in the time ofcircuit-closing is attained by adjusting an actuating lever in relationto the synchronizer, and this application has to do with theconstruction and arrangement of the switch actuating lever, theadjustable support on which it is mounted, and the stationary switchwhich it controls.

Referring more particularly to the drawings in which like referencenumerals refer to the same parts throughout the several views, Idesignates the master lever that is cocked by the setting lever 2 andreleased by the trigger 3, while 4 designates the pin or projection onthe master lever that engages the synchronizer and moves the latter toits set position Where it is locked, as shown in Figs. 2 and 5, afterWhich the synchronizer is released by the master lever, all in the samemanner as in my patent referred to above.

The synchronizer includes the plate 5 that is pivoted on a post 6, andmounted on the synchronizer plate 5 is a pawl 1 pivotally mounted on thepost 8 of the synchronizer plate 5. The pawl 1 includes a tail piece 9engageable with a stop pin l on the synchronizer plate and actuatedagainst the pin by a spring H coiled around the post 8 and having oneend bearing against the pin It! while its other end bears against a lug12 carried by the pawl. When the synchronizer is released and returnedto normal position, the tail piece 9 cannot move past stop pin l0, andpawl l engages the actuating lever in the manner that will now bedescribed.

The actuating lever is mounted on a support or plate l3 that is mountedon the post 6 for adjustment concentrically of the synchronizer plate,and includes an elongated arcuate portion i4 provided with an outwardlyextending finger portion I that underlies the indicating scale IS on thehousing and can be manipulated manually to adjust the support i3 to anyposition, where it is held by the frictional engagement of thesupporting plate with the underlying scale.

Pivotally mounted on the adjustable supporting plate I3 is the actuatingelement that efiects operation of the flashlight circuit-closing switch,and referably this actuating element consists of an arcuate elongatedlever I! that is pivoted at one end on a post l8 carried by thesupporting plate, which is also provided with a guide pin I9 extendingthrough a slot in the actuating lever for limiting movement of thelatter. The switch actuating lever is held in normal position as shownin Fig. 2, with the contacts 28 and 29 separated by means of a spring 2|coiled around the post l3 and having one end engaging a stop 22 on theactuating lever and its other end engaging a lug 23 on the adjustablesupporting r an:

4 plate, the spring 2| acting to maintain the oposite end of theactuating lever normally against the upstanding lug or stop 24. 25designates a cam surface on one edge of the actuating lever located inthe path of the pawl I, which engages the cam surface 25 during returnmovement of the synchronizer and rocks the actuating lever on its pivotI8 to close the flashlight circuit, while the pawl 1 swings on its pivot8 away from the stop l0 and rides over the cam surface 25 during thesetting movement of the synchronizer.

The actuating lever is also provided with an arcuate edge or surface 26generally concentric with the synchronizer and arranged for engagementwith an insulating button 21 carried by the spring contact 25, the outerend of which is arranged to engage the contact 29, the contacts 23 and29 forming parts of a switch that is stationary mounted on and insulatedfrom the housing as shown, the contacts being connected to the jacks 30which are adapted to receive a connector and conductors leading to theusual flashlight circuit and lamps.

The arcuate surface 26 on the actuating lever is of such contour that itis always engaged with the insulating button 21 on contact 28, and as aconsequence, the support IS with the actuating lever movably mountedthereon can be adjusted to any position, depending upon the type offlashlight employed, and the surface 2'5 on the actuating lever isalways in position to move contact 28 and close the circuit, wheneverthe synchronizer is released and the cam surface 25 on the actuatinglever is engaged and moved by the pawl l to rocl; the actuating lever onits pivot.

In this manner, the flashlight circuit is closed by engagement of thecontacts 28 and 29 at any desired instant in relation to the opening ofthe shutter. The contacts 28 and 29 and jacks 30 are insulated from theshutter housing and mechanism, and since engagement of the actuatinglever with contact 28 is through the insulating button 2?, there is nopossibility of short-circuiting the current through the shuttermechanism. With this arrangement, the contacts 28 and 29 can berelatively short, stiff spring elements, and the actuating lever is ofsuch length and so related as to exert sufiicient leverage against thecontact which it engages to move it into positive engagement withcontact 29 and hold the contacts in close engagement for a suflicienttime to insure proper functioning of the lighting elements. The durationof engagement between the contacts depends on the curvature of the camsurface 25 that is engaged by the pawl 1, while the curvature of thesurface 25 is such as to insure uniform and accurate cooperation betweenthe contacts of the switch, irrespective of the position in which theactuating lever way be adjusted or the amount of wear on the parts.

This arrangement enables closing the circuit to the flashlight early inthe movement of the synchronizer mechanism for a lamp having a long lagcharacteristic, as illustrated in Fig. 5, or late in the travel of thesynchronizer mechanism for a lamp having little or no lag andcharacterized by instantaneous lighting, as in Figs. 1 and 2, withoutdisturbing the position of the electric switch which is fixedly mountedon the housing. The contacts can be of stiff, durable construction dueto the structure and operation of the actuating lever which insurespositive and effective engagement of the spring contacts. Thesynchronizer can be disengaged to permit operation of the shutterwithout closing the flashlight circult or the flashlight circuit can beclosed by the master lever independently of the synchronizer, the sameas in my copending application referred to above, and the mechanism forperforming these functions is no different and therefore need not bedescribed.

The present structure makes it possible to employ a simpler, morerugged, and durable construction, having fewer parts than the mechanismof my copending application, and avoids the necessity of adjusting theswitch or of utilizing delicate, flexible, extensible contacts, byutilizing instead a stationary switch insulated from the housing andhaving preferably heavy, stiff spring contacts in conjunction with anactuating lever that is quickly adjustable to any desired position inrelation to the synchronizer and always functions with such powerfulleverage as to actuate the contact which it engages into positiveengagement with the other contact for suificient time to insure properlighting.

While the invention has been described in relation to the particularconstruction herein shown, it is not confined to the details disclosed,and this application is intended to cover such modifications or changesas may come within the purposes of the improvement and the scope of thefollowing claims.

I claim:

1. In a photographic shutter, the combination with a spring-operatedflashlight synchronizer and a flashlight circuit switch permanentlypositioned in relation to the synchronizer and including a pair ofrelatively movable contacts, of a switch actuating lever movableindependently of the switch contacts toward one of the contacts to closethe circuit, said lever having a cam surface located in the path of thesynchronizer and being adjustable endwise to vary the position of saidcam surface along said path.

2. In a photographic shutter, the combination with a pivotally mountedspring-operated flashlight synchronizer and a flashlight circuit switchpermanently positioned in relation to the synchronizer and including apair of relatively movable contacts, of a support adjustable in anarcuate path concentrically of the path of movement of the synchronizer,a switch actuating lever pivotally mounted on said support and movableindependently of said switch contacts, and spring means holding theactuating lever out of operative position, the actuating lever having acam surface in the path of the synchronizer and an arcuate surfaceengaging one of said contacts in any position of adjustment and actingto close the flashlight circuit upon engagement of the synchronizer withsaid cam surface.

3. In a photographic shutter, the combination with a spring-operatedflashlight synchronizer and a flashlight circuit switch permanentlypositioned in relation to the synchronizer and including a pair ofrelatively movable contacts, of a support adjustable in an arcuate pathconcentrically of the path of movement of the synchronizer, an elongatedarcuate switch actuating lever pivoted at one end of the support andmovable independently of said switch contacts, a stop at the oppositeend of the support against which the actuating lever is held, and springmeans engaging the actuating lever and maintaining it against said stop,the actuating lever having a cam surface located in the path of thesynchronizer and an arcuate surface engaging one of said contacts in anyposition of adjustment and acting to close the flashlight circuit uponengagement of the synchronizer with said cam surface.

4. In a photographic shutter, the combination with a spring-operatedflashlight synchronizer and a flashlight circuit switch permanentlypositioned in relation to the synchronizer and including a pair ofrelatively movable contacts, of a switch-actuating member movableindependently of said switch contacts toward one of the contacts toclose the circuit, said member having a cam surface located in the pathof the synchronizer, and a support on which said switch-actuating memberis movably mounted, said support being adjustable along the path ofmovement of the synchronizer and the actuating member being inengagement with said contact in any position of adjustment of thesupport.

5. In a photographic shutter, the combination with a spring-operatedflashlight synchronizer and a flashlight circuit switch permanentlypositioned in relation to the synchronizer and including a pair ofrelatively movable contacts, of a pivoted switch-actuating lever movableindependently of said switch contacts toward one of the contacts and ina direction transversely of the direction of movement of thesynchronizer, said lever having a cam surface located in the path of thesynchronizer, and a support on which the actuating lever is pivotallymounted, said support being adjustable along the path of movement of thesynchronizer and the actuating member being in engagement with saidcontact in any position of adjustment of the support, the synchronizerhaving engagement during its movement with said lever to actuate ittoward said contact.

FRIEDRICH A. GUSTAV PIRWITZ.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,954,673 Krupnick Apr. 10-, 19342,016,834 Morris Oct. 8, 1935 2,171,743 Edwards Sept. 5, 1939 2,218,494Steiner Oct. 15, 1940 2,284,486 Hineline May 26, 1942 2,365,847 SteinerDec. 26, 1944 2,406,691 Jacobson et al Aug. 2'7, 1946'

